Department of Immunization, Wuxi Center for Disease Control and Prevention, Wuxi, China.
Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing, China.
Epidemiol Infect. 2023 Jul 20;151:e125. doi: 10.1017/S0950268823001152.
Varicella vaccination is optional and requires self-payment. On 1 December 2018, Wuxi City launched a free varicella vaccination program for children. This study aimed to evaluate the changes in varicella incidence before and after the implementation of the policy. The data were obtained from official information systems and statistical yearbooks. We divided the period into chargeable (January 2017 to November 2018) and free (December 2018 to December 2021) periods. Interrupt time series analysis was used to conduct a generalised least-squares regression analysis for the two periods. A total of 51,071 varicella cases were reported between January 2017 and December 2021. After the implementation of the policy, there was a statistically significant decrease in the incidence of varicella (β2 = -0.140, P = 0.017), and the slope of the incidence also decreased by 0.012 (P = 0.015). Following policy implementation, the incidence decreased in all age groups, with the largest decline observed among children aged 8-14 years (β2 = -1.109, P = 0.009), followed by children aged ≤7 years (β2 = -0.894, P = 0.013). Our study found a significant reduction in the incidence of varicella in the total population after the introduction of free varicella vaccination in Wuxi City.
水痘疫苗接种是自费的。2018 年 12 月 1 日，无锡市启动了儿童水痘疫苗免费接种项目。本研究旨在评估政策实施前后水痘发病率的变化。数据来自官方信息系统和统计年鉴。我们将该时期分为收费期（2017 年 1 月至 2018 年 11 月）和免费期（2018 年 12 月至 2021 年 12 月）。采用中断时间序列分析对两个时期进行广义最小二乘回归分析。2017 年 1 月至 2021 年 12 月共报告了 51071 例水痘病例。政策实施后，水痘发病率呈统计学显著下降（β2=-0.140，P=0.017），发病率斜率也下降了 0.012（P=0.015）。政策实施后，各年龄段水痘发病率均下降，8-14 岁儿童下降幅度最大（β2=-1.109，P=0.009），其次是≤7 岁儿童（β2=-0.894，P=0.013）。本研究发现，无锡市免费水痘疫苗接种项目实施后，总人群水痘发病率显著下降。
